The invention relates to a vehicle, especially a snow scooter, of the kind that is seen in the preamble of the appended claim 1.
A tracked vehicle of snow scooter type usually has two front laterally spaced-apart skid rails/skis, which are parallel and jointly turnable around a respective substantially vertical axis. Furthermore, the skis are coupled to a steering device to allow a driver of the vehicle to steer the vehicle. The skis support the vehicle from the ground, which usually is snow. Then, the driving of the vehicle is usually composed of a rear centrally positioned track unit having a track that runs all around in the longitudinal direction of the vehicle and is drivingly connected to the engine of the vehicle. The track unit supports the rear part of the vehicle from the ground and offers a driving of the vehicle.
This conventional vehicle structure, having rear track driving and front non-driven steerable skis/runners, has the advantage of offering a simple damping suspension between the chassis and the skis, but the front steerable skis is an acceptable compromise between bearing capacity and steering capacity only at a chosen speed.
GB925032A discloses a tracked vehicle of the kind that is seen in the preamble of claim 1.
WO9318956A1 discloses a snow scooter having two drive-track assemblies in front instead of skis. The object is to improve the steerability as well as to obtain a more efficient suspension of the front part.
Therefore, an object of the invention is to provide a design of a vehicle of the kind in question in order to produce an efficient steering and driving of the vehicle, also at high speeds, while retaining a chosen bearing capacity of the front steerable support members of the vehicle.
The object is attained by the invention.
The invention is defined in the appended independent claim.
Embodiments of the invention are defined in the appended dependent claims.
The spring-damper assembly that supports the drive-track device of the chassis may comprise a four-link mechanism, which carries the body via a joint that offers the support body a turning around a substantially vertical axis, the drive line to the drive-track device suitably having a universal joint or the like at this turning axis. The drive line has naturally also a universal-joint coupling at the transition between the turnable parts of the link mechanism and the chassis, in a manner conventional per se.